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Anilinium-3-carboxyl­ate 3-carb­­oxy­anilinium nitrate

aDepartment of Chemistry, University of Engineering and Technology, Lahore 54890, Pakistan, bDepartment of Chemistry, Government College University, Lahore, Pakistan, and cDepartment of Physics, University of Sargodha, Sagrodha, Pakistan
*Correspondence e-mail: saeed_a786@hotmail.com

(Received 1 November 2012; accepted 1 December 2012; online 8 December 2012)

The title compound, C7H8NO2+·NO3·C7H7NO2, exists in the form of a protonated dimer of two anilinium-3-carboxyl­ate mol­ecules related by an inversion center, and a nitrate anion located on a twofold rotation axis. The bridging H atom occupies, with equal probability, the two sites associated with the carboxyl atoms. In addition to the strong O—H⋯O hydrogen bond, in the crystal, the various units are linked via N—H⋯O and C—H⋯O hydrogen bonds forming a three-dimensional structure.

Related literature

For applications of amino­benzoic acids, see: Congiu et al. (2005[Congiu, C., Cocco, M. T., Lilliu, V. & Onnis, V. (2005). J. Med. Chem. 48, 8245-8252.]); Swislocka et al. (2005[Swislocka, R., Regulska, E., Samsonowicz, M., Hrynaszkiewicz, T. & Lewandowski, W. (2005). Spectrochim. Acta Part A, 61, 2966-2973.]). For related structures and details of their hydrogen-bonding motifs, see: Arora et al. (1973[Arora, S. K., Sundaralingam, M., Dancz, J. S., Stanford, R. H. & Marsh, R. E. (1973). Acta Cryst. B29, 1849-1855.]); Bahadur et al. (2007[Bahadur, S. A., Kannan, R. S. & Sridhar, B. (2007). Acta Cryst. E63, o2722-o2723.]); Hansen et al. (2007[Hansen, L. K., Perlovich, G. L. & Bauer-Brandl, A. (2007). Acta Cryst. E63, o2361.]); Lai & Marsh (1967[Lai, T. F. & Marsh, R. E. (1967). Acta Cryst. 22, 885-893.]); Lu et al. (2001[Lu, T. H., Chattopadhyay, P., Liao, F. L. & Lo, J.-M. (2001). Anal. Sci. 17, 905-906.]); Smith et al. (1995[Smith, G., Lynch, D. E., Byriel, K. A. & Kennard, C. H. L. (1995). Aust. J. Chem. 48, 1133-1149.]); Zaidi et al. (2008[Zaidi, S. A. R. A., Tahir, M. N., Iqbal, J. & Chaudhary, M. A. (2008). Acta Cryst. E64, o1957.]).

[Scheme 1]

Experimental

Crystal data
  • C7H8NO2+·NO3·C7H7NO2

  • Mr = 337.29

  • Monoclinic, C 2/c

  • a = 16.0451 (3) Å

  • b = 4.7575 (1) Å

  • c = 19.7143 (4) Å

  • β = 107.660 (1)°

  • V = 1433.96 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.13 mm−1

  • T = 296 K

  • 0.23 × 0.16 × 0.07 mm

Data collection
  • Bruker Kappa APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.525, Tmax = 0.806

  • 6955 measured reflections

  • 1777 independent reflections

  • 1604 reflections with I > 2σ(I)

  • Rint = 0.017

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.101

  • S = 1.07

  • 1777 reflections

  • 127 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O⋯O1i 0.88 (4) 1.61 (4) 2.4868 (13) 171 (4)
O1—H1O⋯O2i 0.88 (4) 2.55 (3) 3.0686 (14) 118 (3)
N1—H1N⋯O2ii 0.913 (18) 2.027 (19) 2.9157 (13) 164.2 (17)
N1—H2N⋯O2iii 0.944 (18) 1.918 (18) 2.8609 (13) 177.0 (16)
N1—H3N⋯O3iv 0.939 (19) 2.498 (15) 2.9220 (14) 107.6 (11)
N1—H3N⋯O3 0.939 (19) 2.526 (15) 2.9582 (14) 108.3 (11)
N1—H3N⋯O4 0.939 (19) 1.920 (19) 2.8345 (11) 163.9 (13)
C3—H3⋯O2ii 0.93 2.41 3.1189 (15) 132
C5—H5⋯O3iv 0.93 2.58 3.3058 (18) 135
Symmetry codes: (i) -x, -y+2, -z; (ii) [-x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z]; (iii) [-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z]; (iv) x, y-1, z.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97, PLATON and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Amino derivatives of benzoic acid are of considerable importance because of their use as anti-inflammatory and anticancer agents (Congiu et al., 2005). Benzoic acid, its derivatives and their complexes are also used as food preservatives and as antiseptic agents applied in various industrial branches: pharmaceutics, textile and cosmetics (Swislocka et al., 2005). In view of this interest, the crystal structures of various amino derivatives of benzoic acid (Hansen et al., 2007; Lai et al., 1967; Lu et al., 2001; Smith et al., 1995), and their ammonium salts (Arora et al., 1973; Bahadur et al., 2007; Zaidi et al., 2008), have been reported in the literature. The crystal structures of these compounds are characterized by strong hydrogen bonding.

The ammonium salts of 2-aminobenzoic acid are monomers (Bahadur et al., 2007; Zaidi et al., 2008), whereas the chloride salt of the anilinium-3-carboxylate ion (Arora et al., 1973) exists in the form of hydrogen-bonded dimers formed through the carboxylic acid groups of inversion related molecules. In the present study, we attempted to prepare a cerium(III) complex of 3-aminobenzoic acid but the resulting product was a simple nitrate salt of the acid. Herein, we present the crystal structure of this salt.

In the title compound two anilinium-3-carboxylate molecules related by an inversion center are bound to a proton to form a protonated dimer through strong O—H···O hydrogen bonds (Fig. 1 and Table 1). A nitrate anion located on a 2-fold rotation axis is present as counter ion. The bridging H atom (H1O) occupies, with equal probability, the two sites associated with the carboxyl atoms, O1 and O1a [symmetry code: (a) = -x, -y + 2, -z]. The ammonium groups are involved in strong hydrogen bonds to the carbonyl as well as to the nitrate O atoms (Table 1).

In the crystal, (Fig. 2 and Table 1) molecules are linked via N—H..O and C—H..O hydrogen bonds forming a three-dimensional structure.

Related literature top

For applications of aminobenzoic acids, see: Congiu et al. (2005); Swislocka et al. (2005). For related structures and details of their hydrogen-bonding motifs, see: Arora et al. (1973); Bahadur et al. (2007); Hansen et al. (2007); Lai & Marsh (1967); Lu et al. (2001); Smith et al. (1995); Zaidi et al. (2008).

Experimental top

The title compound was prepared by adding one equivalent of 3-aminobenzoic acid (0.07 g) in 15 ml methanol to a solution of cerium nitrate (0.22 g, 0.5 mmol) in 15 ml me thanol. The brown solution was stirred for one hour, after which it was filtered and the filtrate was kept for crystallization at room temperature. The solution was covered with aluminium foil. After 3 days large orange-brown crystals were obtained (M.p. = 492 (1) K). A plate-shaped fragment cut from a large crystal was used for data collection.

Refinement top

The OH H atom was located in a difference Fourier map and refined freely with a fixed occupancy of 0.5. The NH3 atoms were located from a difference Fourier map and refined freely. The C—H atoms were placed in calculated positions and treated as riding atoms: C—H = 0.93 Å with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of the title compound, with the atom numbering. Displacement ellipsoids are drawn at the 50% probability level. Atom H1O has an occupancy of 0.5 [symmetry codes: (a) = -x, -y + 2, -z; (b) -x + 1, y, -z + 1/2].
[Figure 2] Fig. 2. A view along the b axis of the crystal packing of the title compound. Hydrogen bonds are shown as dashed lines - see Table 1 for details [C-bound H atoms have been omitted for clarity].
Anilinium-3-carboxylate 3-carboxyanilinium nitrate top
Crystal data top
C7H8NO2+·NO3·C7H7NO2F(000) = 704
Mr = 337.29Dx = 1.562 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 1777 reflections
a = 16.0451 (3) Åθ = 2.9–28.3°
b = 4.7575 (1) ŵ = 0.13 mm1
c = 19.7143 (4) ÅT = 296 K
β = 107.660 (1)°Plate, pale orange
V = 1433.96 (5) Å30.23 × 0.16 × 0.07 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD area-detector
diffractometer
1777 independent reflections
Radiation source: fine-focus sealed tube1604 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.017
ω scansθmax = 28.3°, θmin = 3.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 2021
Tmin = 0.525, Tmax = 0.806k = 66
6955 measured reflectionsl = 2624
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.037H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.101 w = 1/[σ2(Fo2) + (0.0497P)2 + 1.028P]
where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max < 0.001
1777 reflectionsΔρmax = 0.29 e Å3
127 parametersΔρmin = 0.20 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0050 (11)
Crystal data top
C7H8NO2+·NO3·C7H7NO2V = 1433.96 (5) Å3
Mr = 337.29Z = 4
Monoclinic, C2/cMo Kα radiation
a = 16.0451 (3) ŵ = 0.13 mm1
b = 4.7575 (1) ÅT = 296 K
c = 19.7143 (4) Å0.23 × 0.16 × 0.07 mm
β = 107.660 (1)°
Data collection top
Bruker Kappa APEXII CCD area-detector
diffractometer
1777 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1604 reflections with I > 2σ(I)
Tmin = 0.525, Tmax = 0.806Rint = 0.017
6955 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.101H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.29 e Å3
1777 reflectionsΔρmin = 0.20 e Å3
127 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.03166 (6)0.8054 (2)0.04202 (5)0.0316 (3)
O20.11051 (6)0.75160 (18)0.03226 (4)0.0292 (3)
N10.38230 (6)0.2414 (2)0.11339 (6)0.0256 (3)
C10.09454 (7)0.6963 (2)0.02418 (6)0.0232 (3)
C20.15270 (7)0.4950 (2)0.07568 (6)0.0234 (3)
C30.23625 (7)0.4507 (2)0.07021 (6)0.0241 (3)
C40.29346 (7)0.2769 (2)0.11825 (6)0.0232 (3)
C50.26851 (8)0.1375 (3)0.17048 (6)0.0316 (3)
C60.18493 (9)0.1785 (3)0.17490 (7)0.0355 (4)
C70.12742 (8)0.3602 (3)0.12863 (7)0.0308 (3)
O30.44638 (8)0.7461 (2)0.20141 (6)0.0512 (4)
O40.500000.3567 (3)0.250000.0540 (5)
N20.500000.6216 (3)0.250000.0283 (4)
H1N0.3935 (11)0.384 (4)0.0864 (9)0.045 (4)*
H1O0.014 (2)0.953 (8)0.0144 (17)0.032 (8)*0.500
H2N0.3850 (11)0.075 (4)0.0881 (9)0.044 (4)*
H30.253300.538100.034300.0290*
H3N0.4235 (12)0.243 (3)0.1589 (10)0.043 (4)*
H50.307300.018000.202200.0380*
H60.167200.083000.209300.0430*
H70.072100.391600.133100.0370*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0287 (4)0.0321 (5)0.0368 (5)0.0116 (4)0.0142 (4)0.0065 (4)
O20.0284 (4)0.0300 (5)0.0308 (4)0.0075 (3)0.0113 (3)0.0065 (3)
N10.0214 (5)0.0265 (5)0.0268 (5)0.0049 (4)0.0040 (4)0.0010 (4)
C10.0201 (5)0.0209 (5)0.0281 (5)0.0006 (4)0.0064 (4)0.0005 (4)
C20.0222 (5)0.0215 (5)0.0257 (5)0.0022 (4)0.0059 (4)0.0005 (4)
C30.0232 (5)0.0232 (5)0.0254 (5)0.0021 (4)0.0068 (4)0.0023 (4)
C40.0214 (5)0.0223 (5)0.0247 (5)0.0023 (4)0.0050 (4)0.0022 (4)
C50.0334 (6)0.0322 (6)0.0281 (6)0.0089 (5)0.0078 (5)0.0077 (5)
C60.0390 (7)0.0392 (7)0.0321 (6)0.0062 (6)0.0164 (5)0.0117 (5)
C70.0275 (6)0.0335 (6)0.0340 (6)0.0044 (5)0.0132 (5)0.0038 (5)
O30.0579 (7)0.0333 (6)0.0462 (6)0.0102 (5)0.0086 (5)0.0069 (5)
O40.0663 (10)0.0240 (7)0.0470 (9)0.00000.0196 (7)0.0000
N20.0291 (7)0.0251 (7)0.0286 (7)0.00000.0056 (6)0.0000
Geometric parameters (Å, º) top
O1—C11.2753 (15)C2—C31.3932 (17)
O2—C11.2434 (14)C2—C71.3865 (17)
O1—H1O0.88 (4)C3—C41.3769 (15)
O3—N21.2283 (13)C4—C51.3822 (17)
O4—N21.260 (2)C5—C61.384 (2)
N1—C41.4671 (16)C6—C71.386 (2)
N1—H2N0.944 (18)C3—H30.9300
N1—H3N0.939 (19)C5—H50.9300
N1—H1N0.913 (18)C6—H60.9300
C1—C21.4980 (15)C7—H70.9300
C1—O1—H1O107 (2)C2—C3—C4119.60 (10)
C4—N1—H3N110.7 (12)C3—C4—C5121.15 (11)
H1N—N1—H2N105.5 (16)N1—C4—C3118.84 (10)
C4—N1—H2N109.4 (11)N1—C4—C5120.01 (10)
H2N—N1—H3N112.3 (14)C4—C5—C6118.98 (12)
H1N—N1—H3N110.2 (15)C5—C6—C7120.73 (13)
C4—N1—H1N108.6 (12)C2—C7—C6119.71 (12)
O3i—N2—O4118.83 (8)C2—C3—H3120.00
O3—N2—O4118.83 (8)C4—C3—H3120.00
O3—N2—O3i122.34 (13)C6—C5—H5120.00
O2—C1—C2119.12 (10)C4—C5—H5121.00
O1—C1—C2117.10 (10)C5—C6—H6120.00
O1—C1—O2123.76 (10)C7—C6—H6120.00
C3—C2—C7119.77 (10)C2—C7—H7120.00
C1—C2—C3117.42 (10)C6—C7—H7120.00
C1—C2—C7122.79 (11)
O1—C1—C2—C3158.16 (10)C3—C2—C7—C61.16 (18)
O1—C1—C2—C720.10 (16)C2—C3—C4—N1177.64 (9)
O2—C1—C2—C320.63 (15)C2—C3—C4—C52.25 (16)
O2—C1—C2—C7161.12 (11)N1—C4—C5—C6178.75 (11)
C1—C2—C3—C4177.24 (9)C3—C4—C5—C61.13 (18)
C7—C2—C3—C41.08 (16)C4—C5—C6—C71.2 (2)
C1—C2—C7—C6179.38 (11)C5—C6—C7—C22.3 (2)
Symmetry code: (i) x+1, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O1ii0.88 (4)1.61 (4)2.4868 (13)171 (4)
O1—H1O···O2ii0.88 (4)2.55 (3)3.0686 (14)118 (3)
N1—H1N···O2iii0.913 (18)2.027 (19)2.9157 (13)164.2 (17)
N1—H2N···O2iv0.944 (18)1.918 (18)2.8609 (13)177.0 (16)
N1—H3N···O3v0.939 (19)2.498 (15)2.9220 (14)107.6 (11)
N1—H3N···O30.939 (19)2.526 (15)2.9582 (14)108.3 (11)
N1—H3N···O40.939 (19)1.920 (19)2.8345 (11)163.9 (13)
C3—H3···O2iii0.932.413.1189 (15)132
C5—H5···O3v0.932.583.3058 (18)135
Symmetry codes: (ii) x, y+2, z; (iii) x+1/2, y+3/2, z; (iv) x+1/2, y+1/2, z; (v) x, y1, z.

Experimental details

Crystal data
Chemical formulaC7H8NO2+·NO3·C7H7NO2
Mr337.29
Crystal system, space groupMonoclinic, C2/c
Temperature (K)296
a, b, c (Å)16.0451 (3), 4.7575 (1), 19.7143 (4)
β (°) 107.660 (1)
V3)1433.96 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.13
Crystal size (mm)0.23 × 0.16 × 0.07
Data collection
DiffractometerBruker Kappa APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.525, 0.806
No. of measured, independent and
observed [I > 2σ(I)] reflections
6955, 1777, 1604
Rint0.017
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.101, 1.07
No. of reflections1777
No. of parameters127
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.29, 0.20

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O1i0.88 (4)1.61 (4)2.4868 (13)171 (4)
O1—H1O···O2i0.88 (4)2.55 (3)3.0686 (14)118 (3)
N1—H1N···O2ii0.913 (18)2.027 (19)2.9157 (13)164.2 (17)
N1—H2N···O2iii0.944 (18)1.918 (18)2.8609 (13)177.0 (16)
N1—H3N···O3iv0.939 (19)2.498 (15)2.9220 (14)107.6 (11)
N1—H3N···O30.939 (19)2.526 (15)2.9582 (14)108.3 (11)
N1—H3N···O40.939 (19)1.920 (19)2.8345 (11)163.9 (13)
C3—H3···O2ii0.932.413.1189 (15)132
C5—H5···O3iv0.932.583.3058 (18)135
Symmetry codes: (i) x, y+2, z; (ii) x+1/2, y+3/2, z; (iii) x+1/2, y+1/2, z; (iv) x, y1, z.
 

Acknowledgements

The authors are grateful to Government College University Lahore for providing the X-ray diffraction facility, and to Professor Helen Stoeckli-Evans for valuable discussions.

References

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